The judge presiding over accused killer Peter J. O’Brien’s trial peppered him with "rapid-fire" questions, engaged in a "detailed colloquy" with experts on the stand and "hammered nails" in defense arguments, taking on the role of prosecutor, according to the Supreme Court’s ruling.

"Those questions, which would have been entirely appropriate if propounded by the prosecutor, should not have come from the judge," Justice Virginia Long wrote in the opinion for the majority. "Defendant was entitled to face a single adversary, the State. He should not have had to bear the consequences of a judge who appeared to disbelieve him and his expert witness."

Darren Gelber, a vice president for the Association of Criminal Defense Lawyers of New Jersey called the decision a welcome development for practitioners.

"The opinion signals that judges, by virtue of their position, carry a certain aura with jurors, and when judges spend a lot of time focusing on an issue, I think juries tend to give that a lot of weight," Gelber said.

"I think this opinion will be cited frequently in appeals by defendants when the judge’s questioning goes beyond a few simple questions," Gelber said.

On May 7, 2004, O’Brien picked up the couple at Newark Liberty International Airport as they returned from a winter get-away in Florida, taking them to their home on Crane Way in Toms River, a quiet lagoon-lined block near Barnegat Bay.

Fearing they would soon discover he had stolen $40,000 from them, O’Brien retrieved a five-shot .38-caliber Smith & Wesson revolver and a pillow from his bedroom and proceeded into the office of Anthony J. Napoleon, 57. He shot him from behind several times at close range, according to court papers. His mother, Josephine O’Brien, 54, came out of the bathroom after hearing the gunfire and was shot twice, according testimony from the trial.

As he lay bleeding on the floor, Napoleon looked up and said, "I love you."

"I love you, too," O’Brien said, and left.

Before he died, Napoleon called 911 and implicated O’Brien, who after the killings went to a McDonald’s with friends. There, he was contacted by police and turned himself in less than an hour later, confessing "I did it" in an admission introduced at trial.

Napoleon’s sister, Barbara Bye, had listened to O’Brien’s confession in court. Today, she was distraught with word of the high court’s decision to grant O’Brien a new trial.

"Oh, my God, I just don’t believe it," she said. "He confessed. It’s taped. I mean, what else do they need? And to put a family through this again. It’s five years."

At trial, O’Brien advanced a "diminished capacity" defense. In a taped statement played at a preliminary hearing in August 2005, he explained why he shot the couple.

"I hated my job. I hated what they wanted me to do for a living. ... I hated being around them," he said. O’Brien said they nagged him about his weight, about his lack of chores around the house and about his marijuana use.

The justices noted that judges have broad discretion to intervene in criminal trials, such as when a party’s basic rights are threatened.

"That right is limited — particularly in the context of a jury trial, where the judge is not the factfinder — to ensure that a court does not telegraph to the jury any partiality," the court said.

Bye did not think the judge, state Superior Court Judge James Citta, crossed the line. "I was there the whole time," she said. "He asked for clarification at times. Not in my judgment, and I’m not a lawyer."